Re: Roi Enlarge (without merging) / ROI merging / Edges to ROI conversion

Posted by Michael Schmid on
URL: http://imagej.273.s1.nabble.com/Roi-Enlarge-without-merging-ROI-merging-Edges-to-ROI-conversion-tp3693456p3693461.html

Hi Ghislain,

actually there is a seeded watershed in ImageJ - it is hidden in  
"Find Maxima".

So, initially following Gabriel's suggestion you can
(1) create a mask from the roi (Edit>Selection>Create Mask)
(2) duplicate it
(3) run Filters>maximum to enlarge it
(4) copy it and paste it to the mask
(5) select "Blend" in "Edit>Paste Control.
(Image Calculator > Average is an alternative to steps 5&6)

This will give you particles with the core at value 255 and the  
enlarged rim at 127.

(6) Binary>Find Maxima with "light background", any tolerance below  
127 and output type "Segmented Particles" should do it.


- Convert edges to a roi:
if the edges form closed loops, you can use Analyze Particles with  
"Include Holes" to fill the interior.

Fusing rois: I am not aware of such a tool, it looks like a task for  
a macro examining the Results table. Some simple operations might be  
done by running "Analyze Particles" with different settings  
(circularity) and combining the images created.

Michael
________________________________________________________________

On 26 Nov 2008, at 03:06, Ghislain Bonamy wrote:

> I have seen a couple Threads in regards to modifying ROI. However,  
> I do not
> believe that any of them solves my problem. Resizing ROI to a  
> smaller size
> than there original size is not too hard. However enlarging them,  
> while
> preserving a correct delimitation (not fusing the particle) is a  
> different
> story.
>
> I believe the easiest solution would be to use a seeded watershed  
> algorithm.
> Unfortunately, I cannot seem to find any plugins for that. If you  
> have any
> plugins that may do this I would much appreciate.
>
> I am also interested in a tool to fuse ROI based on there properties
> (circularity, perimeter in common, fluorescence in different channels,
> distance, size...).
>
> On another topic, does anyone have a way to convert edges to an ROI  
> (this
> would probably need a way to provide a seed and to close edges)?
>
> Thanks in adavance.
>
>
>
> --
> View this message in context: <a href="http://n2.nabble.com/Roi-Enlarge-%">http://n2.nabble.com/Roi-Enlarge-% 
> 28without-merging%29---ROI-merging---Edges-to-ROI-conversion-
> tp1579237p1579237.html
> Sent from the ImageJ mailing list archive at Nabble.com.